Cardiac arrhythmias present in the heart disrupt normal rhythm and cardiac efficiency. These arrhythmias can be treated using ablation techniques such as radiofrequency (RF), ultrasound, microwave, pulsed electric field, cryoablation, and other forms of ablation. In the case of ablation techniques that involve the delivery of electrical therapy, a catheter can be used in a multiuse capacity where it serves its primary function of ablation energy delivery, but it can also be used to measure electrograms or aid in location via electrical navigation methods.
However, difficulties arise when attempting to monitor the location of the treatment catheter using navigation programs while the energy delivery is active. For example, RF ablation energy tends to be delivered at a very high level (greater than thirty volts), whereas the navigation signals tend to be used at a very low level (on the order of millivolts). Without apparatus to filter or sequence the navigation signals with respect to the RF ablation energy, the navigation signals are obliterated by the RF energy and are not generally recoverable.